VisSim/Introduction

Vissim screenshot. A sine function and a noise generator are connected by wire to a sum junction and the result is added to a plot block. Via an alternate wire, the signal is filtered with a Butterworth filter and added to the plot block in an alternate color to show the effect of the filter.

VisSim is based around a core product that acts as an interpretive compiler that accepts as input model diagrams saved in files with the ".VSM" extension. The core product, VisSim, is used for general modeling, simulation and control system design applications. It comes with a large library of blocks, which are roughly split into two groups; signal producers and signal consumers. An example of a signal producer is a sine function and an example of a signal consumer is the Plot block. Blocks can be "wired" together and large amounts of blocks can be selected to form a compound block, to ease readability of diagrams.

Most new users of VisSim are interested in the block called the "Plot Block" most of all. This is because most new users are simply running a simulation model in the View-only version of VisSim, and most often the results of any simulation are shown in the plot block. For first time users, therefore, the most important button on VisSim's menu will be the green "Go arrow" used to commence simulation. Depending on the model, the user can change many parameters of a simulation interactively. The View-only version of VisSim looks and feels just like the developer version, except the model cannot be modified. For this reason, VisSim is often used for training purposes and test runs.

For model builders, VisSim's visual interface offers a simple method for constructing and simulating large-scale complex dynamic systems; its math engine provides fast, accurate solutions for linear, nonlinear, continuous time, discrete time, time varying and hybrid system designs. It's layering capablilities enables a hierarchical design that is referred to as model-based development. Using VisSim's statechart view, the UML design can be run in real time.